However extra charges may still apply if consumers exceed their data allowance while abroad.

Chris Wallace has three shops. Mobile phone coverage in two of them flits between a provider in Northern Ireland and a provider in the Republic.

He said: "We're paying around £200 a month for the two business phones, and you're talking between £60-£80 of roaming charges, whether that's data or phone calls, and sometimes we've no coverage at all.

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It will be up to a future government to decide whether to have the EU price restrictions on roaming or not after the UK leaves the EU

"We need our phones. We're out measuring all day and if customers can't get hold of us we lose sales, so we have to have our data roaming on.

"Dropping the roaming charges is going to make a big difference to us.

"At the end of the day, my job is sales and if we're able to sell more curtains and blinds by being able to be in contact with our customers it's better for us and better for our business. "

All 28 EU countries are covered by these new rules, however, the 'roam at home' rule only applies if you manage to stay within your contract.

If you go over your data allowance while on holidays, you could still face a big phone bill on your return.

Pól Callaghan from the Citizens Advice Bureau said the rules are positive, but there are things to look out for:

"If you've got 1,000 minutes of calls that you can use in NI then if you go to France or Spain over the summer, then you should be able to use that 1,000 minutes there as well. The same applies to text messages.

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Pól Callaghan from Citizens Advice said consumers still need to be careful when it comes to data roaming when abroad

"It's really around data roaming where people need to be careful.

"While a lot of the data that people use will be free, there are going to be very specific rules about how much data you can use.

"If you've got 4 or 5 GB of data that you can use in your plan here, it doesn't necessarily mean you've got that much data to use abroad.

"Unless you're going somewhere a little bit more unusual like Iceland or Switzerland, or places that aren't in the EU itself but are in the single market, then it'll be a bit different, and that applies to Turkey as well.

"If you check with your mobile phone provider before go that will keep you right," he added.

But when the UK leaves the EU, it is likely to leave this rule behind. So 'roam at home' will apply until Brexit - after that it is up to the UK government to make its own roaming charge rules.